<ti-select
  #select4
  id="select-sroll-load"
  [options]="options"
  [(ngModel)]="value"
  placeholder="请选择国家"
  [searchable]="true"
  (beforeOpen)="beforeOpen($event)"
  (beforeSearch)="beforeSearch($event)"
  (scrollToBottom)="loadMore($event, select4)"
>
</ti-select>
